Improvement in lifting-jacks



Patented Aug.20,1872-.v

T. MAXON.

Improvement. in Lifting-Jack s.

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THOMAS MAXON, or SPRINGFIELD, OHIO.

IMPRQVE MENT IN LlFTlNG-JACKS.

Specification forming part of Letters Patent No. 130,733, dated August 20, 1872.

To all whom it may concern:

Be it known that I, THOMAS Manon, of Springfield, in the county of Clark and in the State of Ohio, have invented certain new and useful Improvements in Lifting-Jack; and do hereby declare that the following is afull, clear, and exact description thereof, reference being had to the accompanying drawing and to the letters of reference marked thereon, making a part of this specification.

The nature of my invention consists in the construction and arrangement of alifting-jack, as will be herein-after more fully set forth.

In order to enable others skilled in the art to which my invention appertains to make and use the same, I will now proceed to describe its construction and operation, referring to the annexed drawing, which is a vertical section of my liftingjack.

A represents a hollow post cast with the bed-plate B in one piece. In this post moves a bar, 0, up and down, at the lower end of which is a foot, D, projecting through a vertical slot in the front side of the post. This foot is grooved on its sides, as shown, and the sides of the slot in the post enter said grooves,

the foot thus forming a guide for keeping the bar steady in its movement up and down. On top of the post G is a head, E, and the entire rear side of said post is cogged.

The post is raised by the following means: In ears a a on the back of the bar 0 is placed a cogged roller, G, which gears with the cogs on said bar, and on each side of said roller, on

the roller-shaft b, is placed an arm, H, the outer ends of which arms are connected by a rod, e. Between the arms H H, outside of the cogged roller G, is pivoted alevcr, I, the inner end of which is in the shape of two cogs or a double hook, J, fitting in the roller G. This hook is, by aspring, d, drawn against the roller, said spring being attached to the hook and bears against the under and rear side of the rod 6. Between ears f f projecting from the rear side of the post A, above the cars a a, is pivoted a pawl, K, which is drawn against the cogged bar 0 by a spring, h, to hold said bar up at any height to which it may havebeen raised. The lever I being raised it is pressed down, during which movement the hook J turns the roller G, and this in turnelevates the cogged bar the pawl K falling in the cogs holding it up. The article to be raised may be acted upon either by the foot D or the head E, according to its height. WVhen desired to lower the bar 0 the lever I is raised far enough to disengage its hooks J from the roller, and, at the same time, the pawl K is, by its thumbpiece, on, forced away from said bar, when they will readily move downward.

Having thus fully described my invention, what I claim as new, and desire to secure by Letters Patent, is-' The combination of the slotted post A, rackbar 0, with grooved foot D, roller G, swinging arms K, lever I with hook J, pawl K with thumb-piece m and the springs d It, all substantially as and for the purposes herein set forth.

In testimony that I claim the foregoing I have hereunto set my hand this 4th day of July, 1872.

THOMAS MAXON. Witnesses:

HENRY G. FoRBns, AARON BENTZEL. 

